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Old 06-23-21, 05:22 PM
  #24  
Barry2 
LR÷P=HR
 
Join Date: Sep 2019
Location: SF Bay Area
Posts: 2,161

Bikes: 1981 Holdsworth Special, 1993 C-dale MT3000 & 1996 F700CAD3, 2018 Cervelo R3 & 2022 R5, JustGo Runt, Ridley Oval, Kickr Bike 8-)

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Originally Posted by MattTheHat
Do you mean 3%?
How can ambient temperature change a route time by 30%? The only thing I can think of would be if it gets so cold a wet surface freezes or so hot tires melt.
LOL only 3%, I wish it was only 3%

I run a power meter on the bike... I'm NOT guessing !

For every Watt your body places into the bike as power, your body wastes 3.2 Watts as heat. We are not a very efficient engine.
This heat must be cooled or we overheat.
We are AIR cooled and once the ambient rises, the cooling effect drops.
The body will reduce the power output rather than overheat, and the time on the route goes up.

So, ambient temp very much controls your ability to output power and your speed.
This doesn't take into consideration dehydration, which just makes matters worse.

Barry

BTW I'm in California, last week it hit 107F / 41.7C
Body Temp = 98.6F / 37C.
Can you imagine the "cooling" effect of air that is 8F / 5C hotter than you are!

Last edited by Barry2; 06-23-21 at 05:28 PM.
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